Saturday, September 16, 2006

According to information coming from diverse scientific publications, in the last 10 years, has been identified in growing form in almost the whole world, a new strain of Mycobacterium tuberculosis, causing a human Tuberculosis (TBC), multiresistant of extended spectrum (XDR-TB), characterized by their resistance to at least 2 drugs: Isoniazide (INH), Rifampicin (RFP), employees in treatments of first line and at 3 or but drugs of the 6 classes of medications of second line. In other words: resistance to most of well-known antituberculostatics. Hence some specialists label to this illness like: incurable. The previous cases of multiresistance TBC: TB-MDR(4% of the 50 000 cases/year/TBC, in Peru), comprise resistances at 1 or, 2 medications (INH and/or RFP), of first line. Dr. Oswaldo Jave Castillo, Chief of the TB-MDR Unit, of the Ministry of Health (MINSA-PERU), declared yesterday to El Comercio of Lima that from 1997 to the date, 60 cases of XDR-TB had been detected in Peru. Numbers something doubtful (definitively here, a subreport exists) and ridiculous, if it is compared with those 1000/cases XDR-TB/year, in east Europe (250 000 cases/total year/TBC), subsaharian Africa : 8000/year (2 millions cases/total year/TBC) and 12 000 cases each year, in southeast Asia (3 millions cases/year total/TBC). The cases of XDR-TB, frequently happen in patients with incorrect prescripctions, medications of poor quality, irregular treatments, convicts, diabetics, malnourished people, alcoholic, > 65 years, coinfection affections with HIV or inmunosupressed persons, combinations these last ones with rates of high letality. From our point of view, the cases of XDR-TB, were conditioned in our country, for conceptual flaws. It is that up to 1997, the antiTBC fight prioritized standardized treatments(diagnosis -dx- treatments, administration of medications without antibiotic sensibility, treatment), mostly irregular and ineffective. For us, for poor that is a country, the strategies should involve, individualized treatments(dx, studies of sensibility using the economic method : MODS and treatment). Not to forget that an individualized successful treatment costs 2000 dollars on the average, as long as a successful treatment of 1 single case of XDR-TB: 250 000 dollars.

The increment of the morbimortality for TBC, in the entire world has alerted to world organizations of health and others. The problem is specially difficult in Africa where the coexistence of the pandemic of the AIDS, adds but difficulties. The thing is so serious that governments and altruistic people: Olusegun Obasanjo (Nigeria), Gordon Brown (United Kingdom) and Bill Gates (Microsoft),gathered in Davos/Switzerland, to support the Global Plan of fight against the TBC(2006-2015), with a tentative investment of 56 000 million dollars, with the aim of to stop the upward raising of TBC and to reduce the rates of TBC/year, at inferior levels to the current ones. For us the GlobalPlan (more healing than preventive), defers strategies of but value in underdeveloped countries, that is : massive setting-up of individualized treatments, in populational focuses of high population density - concentration of cases - of TBC (Lima, Callao, Loreto, Junin, Ica, Lambayeque, Iquitos), the subsaharian Africa, east Europe,etc., new generations of vaccines, establishing at the same time or next a series of social (glasses of milk popular programs, popular and of quality food programs(fish, cereals, milk and so on) for children, pregnancy woman and old people, buildings good popular housings, universal insurance health, extensive nets of water and drainage, etc), coordinated measures and of long reach.

M. tuberculosis, is a bacteria gram positive, aerobic, of slow growth which dies if it is exposed to the solar light, heat and radiation UV. On the other hand is extremely resistant to cold, freezing or, drying. Our emphasis in the generation of new vaccines rely on the total deciphering of the sequence's genome, of M. tuberculosisthat has allowed to detect possible areas of antigenic variation. With these knowledge and so much money, a serious good option is to develop to the brevity vaccines starting from bacterial DNA, of certain proteins of the cellular (inmunogens) surface and/or attenuated M. tuberculosis. The absence of natural immunity to this germ, is because the human organism through the history didn't have time of establishing appropiate relationships host/germ, with M. tuberculosis. What induces us to differ with Veronique Vincent of the Institute Pasteur of Pariswho affirms that the strains of XDR-TB, appeared 3 000 000 years ago to.C., being dispersed by the first hominids. If Vincent had studied the remains of the first ones hunter-gatherers (20-30 people's dispersed groups) that arrived to America and Peru (20 000 - 13 000 years to.C), she would verify that TBC was almost nonexistent among them. TBC is an illness that develops and generates new strains, where people live very near among them :high populational density (Lima-Callao) or, where the feeding is precarious (southeast Asia, Africa, east Europe). We agree that genomic studies will serve to carry out comparative studies between genomes of normal strains and those of XDR-TB, being possible to discover essential genes, able to confer resistance or aggressiveness to certain strains of M. Tuberculosis, essential knowledge to generate effective vaccines.